A state-of-art DNA Microarray Synthesis and Analysis System (DMS) is requested in al multiuser facility on the campus of Indiana University. No similar system is known to exist in the state of Indiana. Acquisition of the DMS is critical for performing analyses of genome-wide patterns of gene expression in many NIH-funded laboratories at Indiana University. Several of these have already initiated such research, but progress is constrained by lack of available DMS equipment in this region of the country. In addition, several ether NIH-supported laboratories at Indiana University have currently funded grants in which gene expression research involving the DMS or similar equipment has been proposed. For these and other NIH- funded laboratories at Indiana University currently conducting gene expression studies and seeking to incorporate the DMS into their research efforts, the lack of this equipment is becoming an urgent problem. The recent addition of faculty member to the Biology Department with significant experience in setting up and using a similar DMS guarantees that this system will be efficiently incorporated into the gene expression research efforts of laboratories campus-wide. The requested DMS will be ideal for our user group: by utilizing DNA fragment-based arraying approaches, DNA microarrays will be synthesized for a wide range of organisms at reasonable prices. Most NIH-funded users have already incorporated the majority of costs for synthesizing and analyzing heir DNA microarrays into their current NIH grants. Such arrays will also provide us with the flexibility necessary to control the size and composition of our microarrays, synthesizing "mini-arrays" to examine subsets of entire genomes, as needed. The user-friendly DMS will permit all users to perform liquid handling, PCR amplifications, and DNA microarray syntheses themselves, as well as to analyze signals obtained from individual experiments. Housed in a central instrumentation facility of the Indiana Molecular Biology Institute, access to this system will be convenient. The Institute is staffed with a full time supervisor who will oversee daily use of this system, which will be available for meritorious research use University-wide. The NIH-funded projects that will use the DMS include: l) prokaryotic signal transduction, 2) prokaryotic gene regulation by light, 3) regulation of HSF activity, 4) global control of differentiation in Caulobacter, 5) genetics of disease resistance in Arabidopsis thaliana, 6) molecular factors in ovarian cancer, 7) control of gene expression in the early germline of Caenorhabditis elegans, and 8) Radiation repair and meiosis in Coprinus cinereus.